Paleontology in Ohio facts for kids
Paleontology in Ohio is all about finding and studying fossils in the state of Ohio. Ohio is famous for having many different kinds of fossils hidden in its rocks. These fossils tell us about ancient life.
Ohio's fossil story starts very early in Earth's history, during the Paleozoic era, specifically the Cambrian period. Back then, Ohio was mostly covered by warm seawater. Many sea creatures lived here, like brachiopods (shellfish), cephalopods (like ancient squids), coral, graptolites (small colonial animals), and trilobites (ancient sea bugs). Later, bigger animals like bony fishes and sharks appeared.
The first plants on land in Ohio grew during the Devonian period. During the Carboniferous period, Ohio became more like land, with huge swamps and river deltas full of plants. Amphibians and reptiles started living in Ohio then, and they stayed through the Permian period.
There's a big gap in Ohio's rock record after the Permian, until the Pleistocene Ice Age. During the Ice Age, Ohio was home to amazing creatures like giant beavers, mammoths, and mastodons. Even early humans, called Paleo-Indians, lived here and sometimes collected fossils for their mounds.
Many famous paleontologists, like Charles Schuchert, were born in Ohio. Also, many important fossils found in Ohio are now kept in museums around the world. A huge discovery happened in 1965 when over 50,000 Devonian fish fossils were found in Cuyahoga County. The Ordovician trilobite called Isotelus maximus is even Ohio's official state invertebrate fossil.
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Ancient Ohio: A Journey Through Time
Ohio's fossil record begins in the Cambrian Period. No older fossils have been found here. During the late Cambrian, Ohio was underwater, about 10 degrees south of the equator. The sea was shallow and the weather was dry. We don't know much about Cambrian life in Ohio because fossils from this time are mostly found in deep rock samples.
Life in the Ordovician Seas
During the Ordovician Period, Ohio was covered by a warm, shallow sea. This sea was deepest in eastern Ohio. It was like the modern-day Bahamas. Ohio was about 20 degrees south of the equator. Sometimes, small islands poked out of the water in western Ohio. Later, the sea got deeper and covered the whole state, but then it slowly pulled back.
Many fossils from the Ordovician Period are found in Ohio. These include Bryozoans (tiny colonial animals), brachiopods, cephalopods, trilobites, horn corals, snails, clams, echinoderms (like starfish), and graptolites.
The Silurian Period: Changing Seas
Ohio was dry land during the early Silurian Period. But soon, warm, shallow seas returned. Ohio was still about 20 degrees south of the equator. The seas became deeper in the middle Silurian. The northern and eastern parts of Ohio had deeper water than other areas. Between these depths, reefs made of corals and sponges grew. Brachiopods and echinoderms also lived here. By the late Silurian, the seas became shallower again. Other fossils from this time include echinoderms, clams, brachiopods, and cephalopods.
Devonian: Fish and First Land Plants
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In the early Devonian Period, only eastern Ohio was still underwater. Ohio was close to the equator. Brachiopods and echinoderms were still common. By the middle Devonian, the seas had spread across the entire state again. This is when sharks and bony fishes first appeared in Ohio. Giant armored fish called placoderms, like the huge predator Dunkleosteus, swam in these waters.
True land plants also started to grow around this time. As the Devonian Period ended, the sea's currents slowed down, and oxygen levels dropped. This created "stinking seas" where few creatures could live. However, overall, Devonian Ohio had many different animals, including coral reefs, bryozoans, brachiopods, trilobites, cephalopods, clams, crinoids, and ostracodes.
Mississippian: Deltas and Shallow Seas
During the early Mississippian Period, Ohio had many river deltas and flowing water. Later in the Mississippian, a shallow sea covered Ohio. Near the end of this period, the seas left the state. Ohio was still near the equator. Fossils from this time include more land plants, brachiopods, clams, crinoids, and fish.
Pennsylvanian: Swamps and New Animals
Ohio was a low, swampy plain near the coast during the Pennsylvanian Period. It was still close to the equator. Sea levels went up and down a lot, so the rocks show layers from land, freshwater, and sea environments. Fossils of land plants are very common in Ohio's Pennsylvanian rocks. We also find fossils of Amphibians, reptiles, and freshwater clams. Marine life included crinoids, snails, cephalopods, brachiopods, and fish. Trilobites were still around, but their fossils are rare.
Permian: Land and Erosion
By the Permian Period, the sea had completely left Ohio. The water bodies were now lakes and rivers. Southeastern Ohio was a swampy coastal plain. Many plants, like ferns and horsetails, grew here. Ohio was about 5 degrees north of the equator. Sand and mud from river deltas slowly filled in the swamps. Later in the Permian, the land in Ohio was pushed up, and its rocks started to wear away. Permian fossils are not very common, but they include snails, clams, fish, plants, amphibians, and reptiles. Sea fossils from this time are rare.
The Missing Years and the Ice Age
For a very long time, about 248 to 1.6 million years ago, Ohio was above sea level. This means that instead of new rocks forming, old rocks were worn away. Dinosaurs probably lived in Ohio during this time, but we don't have any fossils to prove it. The next period, the Tertiary period, is also missing from Ohio's rock record.
However, during the Quaternary Period, Ohio was shaped by huge glacial ice sheets. A glacier about a mile thick covered the area where Cleveland is today. About two-thirds of Ohio was covered by these glaciers. Whole Pleistocene forests that were buried by glaciers have been found in Ohio. During this Ice Age, Ohio was home to amazing animals like giant beavers, mammoths, mastodons, ground sloths, and even early humans.
Fossil Discoveries and Research
Early Discoveries
One of the most important early fossil finds in Ohio happened between 1837 and 1838. John Locke found the tail of a new type of trilobite while mapping the geology of southwestern Ohio. He named it Isotelus maximus.
Another related discovery happened in 1919. Workers digging a tunnel for the Mad River's Huffman Dam found a giant Isotelus fossil. It was an amazing 14.5 inches long and 10.25 inches wide!
The Great Fish Find
In the spring of 1965, a huge discovery of Devonian fish fossils happened in Cuyahoga County. The state Highway Department, the Ohio Bureau of Public Roads, and the Cleveland Museum of Natural History worked together with Smithsonian scientist David Dunkle. They found as many as 50,000 fish fossils at a construction site! These included giant fish like Dunkleosteus and Titanichthys. By November of that year, over 120 different species had been found, and half of them were new to science.
Ohio's State Fossil
Later, two elementary school teachers and their students helped make Isotelus Ohio's official state fossil. Doris Swabb's third-grade class from Beavertown School in Kettering and Virginia Evers's fourth-grade class from St. Anthony School both visited the Boonshoft Museum of Discovery (which was then called the Dayton Museum of Natural History). After seeing a copy of the huge Isotelus from Huffman Dam, they got the idea to make it the state fossil.
The students wrote letters to their state representatives, Robert L. Corbin and Robert E. Hickey. Both agreed to help make a law. Senator Charles F. Horn also agreed to introduce the idea in the Ohio senate.
Newspapers and TV stations covered the story of the students' idea. Many local geology groups supported it. The Ohio Division of Geological Survey helped write the bill. The bill said that the Isotelus group of trilobites would be the state fossil, not just the one giant specimen. Very few people disagreed with the bill. On June 20, 1985, Ohio House Bill 145 officially declared the trilobite group Isotelus to be Ohio's state invertebrate fossil!
Places to Explore Fossils
- Trammel Fossil Park
People Who Studied Ohio's Past
Many important paleontologists were born in Ohio:
- Erwin Hinckly Barbour was born near Oxford in 1856.
- William Berryman Scott was born in Cincinnati in 1858.
- Charles Schuchert was born in Cincinnati in 1858.
- Walter Hermann Bucher was born in Akron in 1888.
- Erich Maren Schlaikjer was born in Newtown in 1905.
- Stanley John Olsen was born in Akron in 1919.
Museums with Ohio Fossils
If you want to see amazing fossils from Ohio, check out these museums:
- Cincinnati Museum of Natural History & Science, Cincinnati
- Cleveland Museum of Natural History, Cleveland
- Karl Limper Geology Museum, Oxford
- Orton Geological Museum, Columbus
Fossil Clubs
If you love fossils, you might want to join a club!
- Dry Dredgers
- North Coast Fossil Club
